AMPHIBIANS 



255 



while Guppy's Frog (Rana Guppyi) from the Solomon Islands 

 is nearly a foot long. 



The Common Toad (Bufo vulgaris) is a more sluggish animal 

 than the Grass Frog, and better adapted to a terrestrial life 

 (fig. 155). Its skin is dull and warty, and prominent neck-glands 

 like those of the Salamander are present. Teeth are entirely 

 absent. The range of this species is even wider than that of the 

 Grass Frog, for it is found in North-west Africa as well as in 

 Europe and Asia. 



Another species of toad found in Britain, though less fre- 

 quently than the ordinary kind, is the Natterjack (Bufo calami- 

 tata), readily distinguished by a yellow or whitish streak down 

 the middle of the back. The family to which both these toads 

 belong (Bufonidae) is almost as widely distributed as the Ranidae, 

 but is absent from Madagascar and rare in the Australian region. 



There are thirteen other families of the Tailless Amphibia 

 besides those mentioned, but none of them are so widely distri- 

 buted, and some have a very restricted range. 



Order 3. LIMBLESS AMPHIBIANS (Gymnophiona) 



The remarkable modifications which have taken place in the 

 bodies of some Fish-Newts, such as the Siren (see p. 248), are 

 carried a step further 

 here, for the tropical 

 worm-like creatures 

 (fig. 158) which make 

 up the order are en- 

 tirely limbless, tail- 

 less, and modified in 

 other ways for a bur- 

 rowing life. The 

 body of a Caecilian is 

 encircled by grooves, 

 and in some species 

 small bony plates are 



imbedded in the Skin. Fig. 158. A CsedUan (Siphonops anuulata) from tropical America 



The small mouth is 



provided with sharp backwardly - curved teeth suited for the 



capture of earth-worms, insects, and other small creatures. The 



